Group delay compensation filter

Abstract

A group delay compensation filter includes: a waveguide that has a first slot and that is configured to transmit a signal; and a first dielectric resonator that includes: a first dielectric, a first metal layer formed over a surface of the first dielectric, and a first opening provided in the first metal layer, wherein the first dielectric resonator is in contact with the waveguide with the first opening coupled to the first slot, and wherein the first dielectric resonator is configured to compensate group delay in a first frequency band of the signal.

What is claimed is: 
     
       1. A group delay compensation filter comprising:
 a waveguide that has a first slot and that is configured to transmit a signal; and 
 a first dielectric resonator that includes: 
 a first dielectric, 
 a first metal layer formed over a surface of the first dielectric, and a first opening provided in the first metal layer, wherein 
 the first dielectric resonator is in contact with the waveguide with the first opening coupled to the first slot, and wherein 
 the first dielectric resonator is configured to compensate group delay in a first frequency band of the signal. 
 
     
     
       2. The group delay compensation filter according to  claim 1 , wherein
 the first dielectric resonator has a rejection band in the first frequency band. 
 
     
     
       3. The group delay compensation filter according to  claim 1 , wherein
 the waveguide further includes a second slot, wherein 
 the group delay compensation filter further includes a second dielectric resonator that includes: 
 a second dielectric, 
 a second metal layer formed over a surface of the second dielectric, and a second opening provided in the second metal layer, wherein 
 the second dielectric resonator is in contact with the waveguide with the second opening coupled to the second slot, and wherein 
 the second dielectric resonator is configured to compensate group delay in a second frequency band of the signal. 
 
     
     
       4. The group delay compensation filter according to  claim 3 , wherein
 the first slot and the second slot are spaced from each other in a waveguide axis direction of the waveguide. 
 
     
     
       5. The group delay compensation filter according to  claim 3 , wherein
 the first slot and the second slot face each other with a waveguide axis of the waveguide interposed between the first slot and the second slot. 
 
     
     
       6. The group delay compensation filter according to  claim 1 , wherein
 the first dielectric resonator further has a second opening provided at a position which faces the first opening of the first metal layer, wherein 
 the group delay compensation filter further includes a second dielectric resonator that includes: 
 a second dielectric, 
 a second metal layer formed over a surface of the second dielectric, and 
 a third opening provided in the second metal layer, wherein 
 the second dielectric resonator is in contact with the first dielectric resonator with the third opening coupled to the second opening, and wherein 
 the second dielectric resonator is configured to compensate group delay in a second frequency band of the signal. 
 
     
     
       7. The group delay compensation filter according to  claim 3 , wherein
 the second dielectric resonator has a rejection band in the second frequency band. 
 
     
     
       8. The group delay compensation filter according to  claim 1 , wherein
 the group delay is generated at an end portion of a pass band of a band-pass filter.